GULF OF MEXICO - The U.S. Navy MZ-3A Airship flies oil surveillance duty in Gulf Shores, Ala., July 20, 2010. The airship, requested by the Coast Guard to support the Deepwater Horizon Response, serves as a platform for aerial observers monitoring oil to support skimming operations as well as looking for marine mammals and other wildlife that may be in distress. U.S. Coast Guard photo by Petty Officer 2nd Class Gina Ruoti.